In the 1890s Melbourne had an outer circle stream train line connecting parts of the city's east, but lack of demand and saw it shutdown.

Now, with state and federal elections on the horizon and an ever-growing population, Labor is promising to revive the concept.

Opposition Leader Bill Shorten on Sunday promised an extra $300 million towards planning the suburban rail loop if he wins the next election "to turn the dream of suburban circle railway for Melbourne into a reality".

The cash matches that already promised by Victorian Premier Daniel Andrews in August to get the ball rolling on a high-speed rail line through Melbourne's east, looping to the west.

Double the money means double the resources to finalise exact station locations, route alignments, rolling stock and staging for the $50 billion, 30-year project according to the two Labor leaders.

"We may even be able to make a start (on construction) earlier than 2022," Mr Andrews told reporters on Sunday.

Construction on the loop is expected to start in 2022 but it won't be completed until 2051.

The 90km underground train route would link Cheltenham in the southeast to Werribee in the southwest and connect to the proposed Melbourne Airport rail line, with up to 12 new underground stations.

Stations in the west of the city are sparse, but Mr Shorten and Mr Andrews said planning might reveal options for more stops, particularly since the planned airport rail will see parts of the network electrified.

Up to 400,000 passengers a day are expected to use the proposed loop.

Victoria goes to the polls on November 24 and population, congestion and cost of living are shaping to be major issues.

State Opposition Leader Matthew Guy on Sunday promised free text books for public high school students worth nearly $3000 per child over six years.

"It's a way of investing in our future and giving our kids the best opportunities through the state school system," Mr Guy told reporters.

The program would not be means tested, instead books would be bulk-ordered for schools which would then lend them out to students.

The books would be returned at the end of the year for re-use if still current.

Mr Guy said planning for the program would happen in the first year of government if he is elected and would start in 2020.

The program will be phased in over two years by year level starting in 2020 with Stage 1 for students in years 7-9 and Stage 2 for students in years 10-12.